A hybrid vehicle is known which can travel using a drive source of at least one of an engine and a motor generator and in which a drive system is constructed by connecting the engine, a first clutch, the motor generator, a second clutch and drive wheels in this order. In such a hybrid vehicle, an EV mode in which the vehicle travels using only the motor generator as a power source is set by releasing the first clutch and engaging the second clutch to stop the engine, and an HEV mode in which the vehicle travels using the engine and the motor generator as power sources is set by engaging both the first and second clutches.
When the vehicle starts in the above HEV mode, the drive force of the engine may be suddenly transmitted to the drive wheels to cause a shock associated with a torque variation if the second clutch is switched from the released state to the engaged state. To prevent this, it is disclosed in JP2007-15679A to control the second clutch to be in a slip engagement state when the vehicle starts in the HEV mode (WSC control).